We just packed up the family and left to visit extended family a couple of states away. Took our relatively new Garmin Vist Cx GPS with us, and am very happy to report we had a great experience with the device. Using the Garmin City Navigator v8 software I preloaded routes to Grandma's house and the maps needed to cover the main roads between here and there. The device was able to automatically calculate new routes when we made a bad turn. We could search for the nearest gas stations or Wendy's in real-time based on where we were at. Plus we could always answer the question of "are we there yet"!
I'll post some more about the trip and the use of GPS later, but wanted to get this up now. Really fun stuff, worked better than I had expected.